Pretty good! Maybe ensure there no repeat colors on competitor cars so it is easier to distinguish. Also, have you considered adding Mario Kart like rubber-banding to match difficulty to player skill level?

@agustín-pérez-fernández Hello, thanks the feedback. Yeah sadly there was a short time while it was bad, in some reason it just didn't worked without SSL certificate on my site - I don't know why and how - but I added it and it works well again.